A race car accelerates from 0 m/s to 30.0 m/s with a displacement of

Physics

1 answer:

worty [1.4K]3 years ago

6 0

Answer:

4. 10.0 m/s²

Explanation:

I) if initial velocity is 'v₀', the final velocity is 'v', the accelaration is 'a', the distance is 'L' and elapsed time if 't', then:

$1. \ a=\frac{v-v_0}{t};$

$2. \ L=\frac{at^2}{2}.$

II) using these two equations after substitution v₀=0; v=30 and L=45:

$\left \{{{45 =\frac{at^2}{2}} \atop {a=\frac{30-0}{t} }} \right.$

$\left \{ {{at^2=90} \atop {at=30}} \right. \ \ \left \{ {{a=10} \atop {t=3}} \right.$ $=> \ a=10\frac{m}{s^2}$

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Archy [21]

Answer:

V = 4.81 V

Explanation:

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As the current draw is larger, the loss in the internal resistance will be larger too, so the potential difference between the terminals of the battery will be lower.

5 0

3 years ago

Find the unit vector in the direction of vector B=4i+2j-5k

solmaris [256]

Answer:

$\frac{4}{\sqrt{45} } i\,+\frac{2}{\sqrt{45} } j-\frac{5}{\sqrt{45} } k$

Explanation:

for the unit vector, we need to divide the given vector by its norm, because it should be in the SAME direction as the original vector, but of magnitude "1".

We notice that the norm of the given vector is:

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